glowing end of cat?

[S14Driftn4life]

so i started my car for the 1st time after a full rebuild and the car started of with a very rough ilde, this started to get better and better after it sat for a while. keep in mind this is a .30 over ka24de full machine block and head so i was kinda expecting this. but im 99% sure the timing is fine.
my concern is that after it was sitting at 1500ish rpms for 20min or so i looked under the car and the rear most part of the cat was glowing red??
any ideas? it didnt do this before.
as for the idle does this sound normal after a complete rebuild? it sounds like its loping but it is slowly getting better and less and less smoke.
had a light fly on it but now it has the light pully kit too so maybe the extra loss of weight?

HELP

[Sileighty_85]

either engine is running too rich or the Cat is clogged and melting inside.

[Hywarp161]

^^^^what he said.

[dudewutup]

ive got an extra cat, pm me if you need it

[Touge Whore]

Yeah, if you believe your timing is right, I would look to the fuel mixture and the cat itself.